Jasper is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. This mineral breaks with a smooth surface, and is used for ornamentation or as a gemstone. It can be highly polished. When the colors are in stripes or bands, it is called striped or banded jasper. Jasper is basically chert which owes its red color to iron inclusions.

Volcanicly heated water is generally thought to be required in the formation of jasper.

The original materials are often fractured and/or distorted after their original formation and are later filled with other colorful minerals resulting in a myriad beautiful patterns.

Picture jaspers exhibit combinations of patterns (such as banding from flow or depositional patterns (from water or wind), dendritic or color variations) resulting in what appear to be scenes or images, on a cut section.




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